It is well known in the beer brewing industry, particularly in the homemade or small-scale beer making industry that the method for making beer may generally include four steps, which may occur in four different vessels.
The first step is heating of water. This heating may occur in a vessel sometimes referred to as a ‘hot liquor tank’ or ‘hot liquor kettle’. Water in the kettle may be heated by such means as a flame under the kettle or electric element under or in the kettle. The heated water in the hot liquor kettle may serve functions such as providing a ready source of warm water for mashing, providing a source of warm water to rinse the grain in order to remove sugars after mashing is completed, and acting as a reservoir for regulating the temperature of the mashing process. The hot liquor kettle can regulate the temperature of the mash by the use of a coil or tube, often made from copper or stainless steel or other heat-conductive material that is immersed in the reservoir of warmed water. Cooler liquid from a mash tun is circulated out from the mash tun through the coil or tube immersed in the reservoir of warmer water, picking up heat from the warm water through the walls of the coil or tube and returning to the mash tun where it is combined with the rest of the liquid, raising the temperature in the mash tun to the desired temperature.
The second step is mashing the grain, which may occur in a vessel referred to as a ‘mash tun’. Grain is combined with warm water in the mash tun to allow enzymes to interact with carbohydrates in the grain, producing a sweet liquid called ‘wort’. The wort is transferred to the boil kettle for boiling. A mash screen in the mash tun holds the grain back so that it is not transferred to the boil kettle along with the wort.
The third step is boiling the wort, which may occur in a vessel referred to as a ‘boil kettle’. Reasons for boiling of wort may include sanitizing the wort, reducing the volume of wort, and altering the flavor of the wort. Following the boiling of the wort, it needs to cool on its own or be chilled to a lower temperature before yeast can be added.
The fourth step is fermenting the wort to produce beer. This may occur in a vessel, which is called the ‘fermenter’. Fermentation may occur in a cylindro-conical vessel with cylindrical sides and conical base. Such a vessel may also be referred to as a ‘conical fermenter’.
The production of fermented beverages, such as beer, generally adheres to the following procedures or methods.
During the mashing process, it is generally recognized that it is desirable to regulate the temperature of the liquid during the mashing process to achieve such ends as optimizing the enzyme activity. Heat is constantly lost from the mash tun to the surrounding environment and may need to be replaced to keep the desired or target temperature in the mash tun. The temperature in the mash tun may be raised by employing a heat source directly underneath the mash tun, or by circulating liquid out of the mash tun and heating it before it is returned to the mash tun. It is also known that it is often desirable to provide a means of agitating or moving the grain or liquid in the grain bed so that the enzymes are provided optimal exposure to and interaction with the complex carbohydrates and to help keep the mash more fluid. This increases the efficiency of the conversion from complex carbohydrates into less complex sugars and allows for optimal recovery of sugar from the grain. And it is also know that prior to transferring to the boil kettle, the wort is often circulated for a suitable period of time through the grain, past a screen that holds the grain back, out of the mash tun, and then back into the mash tun on the far side of the grain. This process, also known as lautering, can serve purposes such as changing enzyme interaction with carbohydrates, leading to altered conversion of complex carbohydrates into sugars that can be digested by brewer's yeast, and clarifying the wort by removing suspended grain particulate or sediment by filtering it out in its passage through the grain.
In the homemade or small-scale beer making industry, mashing generally occurs in a vessel that is dedicated to mashing often called a mash tun. The mash tun is separate from other vessels such as the hot liquor tank that is used to heat water, the boil kettle that is used to boil the wort, and the fermenter that is used to ferment the wort into beer. Once the mashing is complete, the wort may be transferred to the boil kettle where it is boiled in preparation for fermenting.
One notable exception to the above method for mashing is the method or process sometimes referred to as ‘brew in a bag’ or by the acronym ‘BIAB’ that entails placing a porous bag, such as might be made from nylon mesh, directly in the pot or kettle. This might be the same pot or kettle in which boiling of the wort will later occur. The bag is filled with grain and the kettle filled with water. The top of the bag is secured in some fashion such as attaching it to the top of the pot or a hook above the pot so that grain does not escape from inside the bag. A heat source may be applied at the bottom of the pot to warm the temperature of the liquid inside the pot or kettle. A mash screen may be inserted at the bottom of the pot or kettle, to keep the nylon bag from melting on the pot heat source. The mashing occurs in this vessel and when complete, the bag is removed from the pot or kettle. As the bag is withdrawn, wort flows out of the bag, remaining in the pot, and the mesh bag removes the majority of the grain with it. The wort remains in the vessel where it will then be boiled in preparation for fermentation. This method or process is desirable by some for reasons that might include taking up less space, being considered easier to execute, and requiring less equipment than the traditional methods, since in addition to a pot or kettle, a separate mash tun and hot liquor kettle are not necessary.
After the mashing process is completed, the sweet liquid generally referred to as wort may be transferred to a vessel called a boil kettle. It is well known in the beer brewing industry, particularly in the homemade or small-scale beer making industry that a reason for boiling of wort is to sanitize the wort. It is also known that following the boiling of the wort, it needs to be chilled to a lower temperature before yeast can be added. And thirdly, it is also known that for many beer types it is important to maintain sanitary conditions throughout the chilling period to reduce or eliminate possible sources of contamination, which might spoil the beer.
In the homemade or small-scale beer making industry, wort is generally boiled in a vessel that is separate from the fermentation vessel. This vessel is generally referred to as the boil kettle. The boil kettle shape is generally with side walls of cylindrical shape with a flat bottom joined to side walls by a radiused corner. This shape is generally similar to what are sometimes referred to as soup or stock pots. Ports or fittings can be added to the boil kettle for purposes such as inserting apparatus for reading the temperature or addition or removal of liquid.
Once the wort has been boiled, it needs to be chilled to a temperature that is suitable for the healthy growth of yeast. It needs to be chilled in a reasonable amount of time to reduce the potential for contamination.
There are at least three methods that might be employed by brewers in the homemade or small-scale brewing industry for the chilling of wort once boiling is completed. In the first, the boil kettle itself can be physically transported into a chilling media, such as an open-air cold-water bath, which can be made in a sink or tub. A chilling media such as cold tap or ice water is kept surrounding the metal boil kettle and heat is transferred from the hot wort to the chilling media through the metal walls, cooling the wort in the process.
A second method for the chilling of wort is to insert in the wort a tube, often coiled, and often made of copper or stainless steel, through which a chilling media such as cool water is ran. As the chilling media passes through the immersed tube, heat is transferred from the wort to the water through the walls of the metal tube, cooling the wort in the process.
A third method to chill wort is to use a heat exchanger located outside the boil kettle. A hose or pipe is connected from the boil kettle to the heat exchanger and a second hose or pipe is connected from the heat exchanger to the vessel where fermentation will take place. A second set of hoses transfers a chilling media to and from the heat exchanger. The hot wort leaves the boil kettle through the hose or pipe and enters the heat exchanger where the wort passes on one side of a metal dividing wall or partition (often made of copper) and a chilling media (often water) passes on the other side of the dividing wall or partition. Heat is transferred from the hot wort to the cooling media through the dividing metal wall or partition.
Once the wort has been chilled, it is transferred to the fermenting vessel. In the homemade or small-scale brewing industry, the most common fermentation vessels are sealable plastic buckets, glass carboys, or cylindro-conical metal vessels with cylindrical side walls and conical base. Prior to the addition of wort, the fermentation vessel may need to be sanitized so that undesirable microbes do not contaminate the freshly chilled wort. Various means for sanitizing can be used, but the most commonly used in the homemade or small-scale beer making industry is the use of physical or chemical cleaning followed by the introduction of chemical sanitizers. The use of a chemical cleaner or sanitizer may present a drawback since if it is not thoroughly rinsed off, it can end up in the beer as an off flavor or toxin.
The existing equipment and/or methods for making a fermented beverage, such as beer, can suffer from one or more drawbacks. First, the equipment and/or methods can require plural vessels to complete the process of mashing, boiling, chilling and fermenting (hot liquor tank, mash tun, boil kettle, chiller, fermenter). This can add cost and necessitate additional storage space when not being utilized for brewing. Second, the equipment and/or methods can require close supervision or automation at points of the process to regulate temperature, liquid flows between vessels, and liquid levels. Third, the equipment and/or methods can require transferring of liquid between vessels during the brewing process, which can be a messy and time consuming process. Fourth, the equipment and/or methods may not provide an adequate mechanism to filter grain particulate to prevent it from passing into the boil kettle, leading to undesirable compounds in the wort. Fifth, the equipment and/or methods may not provide an easy means of maintaining precise temperature in the mash tun. Sixth, the equipment and/or methods can require the dangerous physical moving of a boil kettle containing hot wort. Seventh, in the equipment, the lid cannot be securely placed on the boil kettle during chilling due to the entry of tubes for chilling media, and the sanitized wort is therefore exposed to the open air and can become contaminated by airborne pathogens. Eighth, there can be an increased risk for compromising sanitation as the additional hardware necessary for chilling the wort may introduce pathogens to the sanitized wort. Ninth, the equipment and/or methods can require additional cleaning and setup which is time consuming and costly. Tenth, the equipment and/or methods can require chemical sanitizing of the fermenting vessel, which may lead to off-flavors in the beer.